Resilient calk for horseshoes



May 14, 1935. c. G. AKERBERG 2,001,118

RESILIENT CALK FOR HORSESHOES Filed April 19, 1934 G'df/ G A kerberyPatented May 14, 1935 PATENT OFFICE RESILIENT CALK Fort nonsssnons (EarlG. Akerberg, Oshkosh, Wis, assignor to Giant" Grip ManufacturingCompany, sh

kosh, Wis, a corporation of Wisconsin 1 Application April 19, 1934,Serial No. 721,386

. t t 3 Claims.

The present invention relates to improvements detach-ably secured to;the under side of the horseshoe.

isfactory, however, due to the rather hard and Suchcalks haveprovenpartially-unsatinsufiiciently resilient nature of the paddingemployed, and to the lack of strength; and durabili-ty ofthe entirestructure. Further, serious difiiculties tantamount to. iailure; havearisen, in most instances in the manner of securing the pads to thehorseshoes.

Prior means, for fasteningpadded calks to horseshoes, have consisted of,metal inserts embedded in the pad portions of the calks. and having.integral extension-s which are secured in the horseshoes. Failure hasoccurred consistently in most of such. priordevices due to. crushing orspreading of the metal inserts when subjected to. the heavy load imposedby the horse. Nondeformable. inserts have-beenprcposed but they havebeen too heavy andtoo difiicult tobond securely and properly withinthepad.

It is therefore aprimary object of the present invention to provide aresilienthorseshoecalk in which the metal'insert is securely fastened inthe resilient pad, and prevented from deforming Another object of theinvention is to devise a detachable'horseshoe calk member having onepart thereof firmly and noncrushably anchored in a resilient pad, theother part forming an ex- 7 tension to matewith the horseshoe. Y

A further object of this invention resides in the provision-ofahorseshoecalk of maximum resilience and wherein a amount of metalstructure is employed.

A still further object of the inventionis the provision of a detachablehorseshoe call; in which .the metal insert embodies. means for'verysecurely anchoring the insert to the resilient pad 'while simultaneouslyreinforcing said insert.

Another object of the present invention is to devisea' horseshoe call:of maximum strength in the bond between the resilient pad and themetallic insert.

A still further object of my invention is the provision of a horseshoecall; of great strength is constructed in general of two main parts,

and resilience which is yet simple and inexpene sive to manufacture.

It is another object of myinvention to devise a simple horseshoe call:insert which is so. do;- signed as to permit the satisfactory use of apad oiunusually great resilience. 7

With the above and other objects in view the detailed descriptionwillproceed, reference be-. ing made to the accompanying drawing in whichlike reference characters are employed to denote like parts throughouttheseveral views.

Figure 1 is a bottom plan view of a horseshoe provided with a detachablecalk embodying the present invention.

Figure 2 is a partially fragmentary sectional view taken on the line 2 2of Figure 1 and showing in elevation the metal insert embedded in theresilient pad.

Figure 3 is a view similar to Figure 2, but illustrated in completesection. 2

Figure 4 is a sectional view taken on the line 4..4 of Figure 1 and atright angles to the plane of; Figure 3/ g Figure 515 a top plan view ofthe metal insert and its reinforcing means Figure 6 is a bottom planView of the insert shown in Figure 5. i

Referring now to Figure 1 of the drawing, reference numeral lldesignates a horseshoe of the conventional type having on its forwardpart 30 spaced apertures l2 which are tapered upwardly and inwardly. Therear portion of the horseshoe is provided with similar apertures It. Adetailed disclosure of these apertures can be obtained by reference toPatent No. 1,875,405, granted September 6, 1932.

1 As illustrated, the forward openings l2 are adapted to receiveindividual conventional drive calks M of all-metal construction, butwhich may .well take the form of special resilient calks (not shown),embodying the present invention if desired. fThe openings l3 in the heelof the horseshoe are adapted to receive a resilient bar pad, indicatedgenerally at i ii, which has been selected to illustrate the major partof my invention. .Various other types of pads are adapted to embody theinvention. I Y

The resilient bar'pad or calk IE comprises two symmetrical sections l1.and H! which are joined by the bridge portion l9. Each of the sectionsill and It isfirmly secured to the horseshoe H in a manner presently tobe set forth.

. With additional reference now to Figures.26 of the drawing, it will beseen that the call: [6

exterior face of the flange 2?.

namely: a resilient pad 2| and a plurality of metallic inserts 22 whichwill now be described in detail.

The pad 2|, composed. of resilient and shock absorbing material is forthe purpose of dampening shocks and jars and absorbing other undueimpacts which normally would be transmitted to the horse by means of theconventional metal shoe. I have found in practice that rubber serves asthe best known material in forming the pad 2|. I have found further thatrubber of a hard or semi-hard nature is undesirable for several reasons,but that until the time of my improvement an undesirably hard rubber wasthe only kind that could flnd practical use.

One of the cardinal objections to the use of semi-hard rubber is itslack of sumcient resilience and its failure to properly absorb shock. Asit is a primary purpose of my invention to devise a calk of maximumresilience and shock absorbing qualities, it will be apparent that theuse of hard rubber in the construction would defeat the principal aim ofthe invention. Another serious objection to the use of hard rubberarises from its proclivity to chip and crack under pressure. Thistendency has caused failure of previous calks due to the cracking of therubber adjacent the metal insert and subsequent tearing loose of theinsert from the pad. A semi-hard rubber further lacks theground-gripping action or traction that can be obtained with a softerrubber, due to the fact that soft rubber may be deformed sumciently inoperation to spread the pad into substantially full and balancedengagement with uneven surfaces. The desirability of utilizing softerrubber may have been recognized heretofore, but to my knowledge no onehas succeeded in devising an anchoring means or joint for securing sucha pad firmly and permanently to the horseshoe. With my improved calkconstruction, however, I have found it feasible to use a grade of rubberwhich is much more soft and yielding than has heretofore been deemedpossible, thus overcoming the serious faults above set forth.

The metallic inserts 22 function to secure the resilient pad 2| to thehorseshoe I i. To this end each insert comprises a split flanged lowerportion 23 and an upper extension 24, represented in the specificembodiment shown as being hollow in nature. responding aperture l3 inthe horseshoe heel to securely fasten the pad [6 with respect to thehorseshoe.

The method of forming the metal inserts is of such nature as to providean extremely simple and inexpensive process of manufacture. Each insertis stamped in one operation from a single metal blank. The forming diespress the central portion of the blank into the configuration shown bythe extension 24 of Figures 2, 3 and 4. Simultaneously the end portionsof the blank are pressed outwardly to form wing-shaped flanges as at 21and 28 and are provided with holes 25 and 26 for a purpose that willpresently become apparent.

Extending between wing flanges 2'! and 28 of each insert and throughholes 25 provided therein is a rivet 29. The head 3! of rivet 29 liesagainst the outside surface of the flange 28, while the swagged end 32of the rivet bears against the It will readily be seen that in thismanner each rivet functions to prevent spreading of the flanges 27 and28 with respect to each other and acts in effect as a tie rod betweenthe said flanges. Each rivet further Each extension 24 mates within acor- 1 acts as an additional anchoring means in the resilient pad aswill presently be set forth.

As previously stated the flanges 21 and 28 of each insert 22 areembedded in the resilient pad 2|. In the embedding operation theresilient material is allowed to flow up into the hollow extension 24 ofthe insert, thereby imparting added strength and durability to the saidextension and to the joint. Further, the flow of resilient material intoextension 24 strengthens the bond between the insert and the pad,thereby increasing the strength of the calk construction as a whole anddiminishing the possibility of the metal insert tearing loose from theresilient pad.

As will be readily appreciated from an inspection of Figure 3 of thedrawing, when the detachable calk is assembled with respect to ahorseshoe, a severe load is imposed upon the metallic insert 22 due tothe weight of the horse. In consequence a reactive stress of appreciablemagnitude is developed in the metal insert and the tendency to strain ordeform becomes very great. In prior inserts the deformation of themetallic inserts has been so great as to cause separation of the flanges21 and 28 thereof, accompanied either by crushing of the whole insert orseparation of the pad from the insert.

By means of my improved structure these defects have been obviated. Theentire insert has been greatly strengthened and the bond between themetal and rubber made more secure due to the added anchoring action ofthe rivet embedded in the resilient pad.

The bond between the insert and the resilient pad is furtherstrengthened by means of the holes resilient pad since under workingloads the flanges have no tendency at all to contract but tend to spreadapart as far as the limitations imposed by the rivet 29 will allow.

Another great advantage deriving from my improved construction residesin the fact that the inserts 22 may have but a shallow anchor inresilient pad 2| and still retain the strength of bond with the saidresilient pad necessary under the most severe working conditions.

insert anchor increases the depth of resilient padding available foractual road wear. I have found in commercial use that the resilient padmay be worn down to within A, of its bottom face and still giveexcellent results. be seen that my improved detachable calk constructionaffords a calk not only of increased strength and resilience but oflonger life as well.

It will be readily appreciated that a shallow 7 It will thus I havefound it desirable in forming the inserts of the present invention toemploy blanks of relatively thin metal. By using inserts which areformed from relatively thin metallic blanks, and which are anchored toonly a shallow depth in the pad portion of the calk, an assemblycomprising a minimum of metal and a maximum of padding is produced. Itwill be quite obvious that such an assembly is marked by a maximum ofresilience, especially in view of the malleable nature of the smallamount of metal which is employed. Further benefits resulting from theuse of thin shut metallic inserts reside in the consequent economies ofmanufacture and the decrease in weight of the calk assembly.

To summarize briefly, my invention provides a essential characteristicsthereof.

greater durability, lighter weight, superior resilience, and longer lifethan any heretofore produced; and therefore it will be apparent that thesuperior quality of service rendered by my improved calk, coupled withthe greatly increased economies in manufacture and use of the same,constitute a distinct and important advance in the art.

As. the present invention resides chiefly in an improved anchoring meansand the better complete calks that can be produced as a result thereof,it is obvious that various other types of pads may be substituted forthe illustrated flexible bar pad. For example, pads such as thosedisclosed in Patent No. 1,777,727 to Krug, et a1., may be utilized, butin all of such instances, a rubber will be used that preferably issofter than has heretofore has been considered practicable.

The invention may be embodied in other specific forms without departingfrom the spirit or The present embodiment is therefore to be consideredin all respects as illustrative and not restrictive, the scope of theinvention being indicated by the appended claims rather than by theforegoing description, and all changes which come within the meaning andrange of equivalency of the claims are therefore intended to be embracedtherein.

What is claimed and desired to be secured by United States LettersPatent is:

1. A horseshoe calk comprising a resilient pad member; a metallic inserthaving a hollow upper extension for engagement with a horseshoe andlower flanged portions embedded in said pad and providing a concavityfor receiving some of the resilient material of said pad; and meansinterconnecting and reinforcing said flanged portions and adapted tostrengthen the bond between said pad and said flanged portions byretaining said pad material within said concavity.

2, A horseshoe calk comprising a resilient pad member; a metallic inserthaving a split upper extension for engagement with a horseshoe and lowerwinged anchoring portions bonded in said pad and providing a concavityfor receiving some of the resilient material of said pad; and meansinterconnecting said winged portions and adapted to restrain said wingedportions against relative displacement and to increase the strength ofbond between said pad and said winged portions by retaining said padmaterial within said concavity.

3. A horseshoe calk comprising a relatively soft and unusually resilientpad member; a metallic insert having a recessed upper extension forengagement with a horseshoe and lower flared portions of relatively thinmetal anchored in said pad and providing a concavity for receiving someof the resilient material of said pad; and means interconnecting andreinforcing said flared portions and serving to strengthen the anchorageof said flared portions in said pad by retaining said pad materialwithin said concavity.

CARL G. AKERBERG.

